Nerve treatment methods

ABSTRACT

The present disclosure is directed to the use of fusogenic compounds such as polyethylene glycol (PEG) in combination with antioxidants, calcium-containing and calcium-free solutions for treating damaged nerves, such as for reconnecting severed nerves.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication No. 61/578,930 filed Dec. 22, 2011 and U.S. ProvisionalPatent Application No. 61/446,803 filed Feb. 25, 2011, the disclosuresof which are hereby incorporated by reference in their entirety.

STATEMENT OF FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

BACKGROUND OF THE DISCLOSURE

The present disclosure generally relates to a nerve coaptation apparatusand, more particularly, to a microsuture-less nerve coaptation apparatushaving relatively-movable coupling members to inhibit nerve compressionin the event of, for example, nerve swelling.

Microsurgery (that is, surgery aided by use of a microscope) is used invarious types of medical procedures that treat relatively small bodilystructures, such as coaptation of severed nerves. In this case, theprocedure typically involves using a relatively small suture to connectthe severed ends of the severed nerve segments. This facilitates axonalgrowth to fuse the nerve segments, which ideally restores some degree ofnerve functionality.

Unfortunately, nerve coaptation microsutures have several limitations.For example, connecting severed nerve segments with a microsuture is arelatively long procedure that requires considerable surgicalexperience. Furthermore, the outcome of such procedures are typicallyconsidered poor due to relatively long recovery times (for example, upto several years) and limited nerve functionality (for example, lessthan 20 percent of original nerve functionality).

Nerve coaptation couplings have been proposed for use in addition tomicrosutures in an attempt to address the above limitations. Suchcouplings typically include a sleeve that houses and isolates the endsof the severed nerve segments, and pharmaceutical agents can beincorporated into the sleeve to promote axonal growth. Unfortunately,such devices inhibit nerve swelling proximate the ends of the severednerve segments, which inwardly compresses the nerve segments and canadversely affect nerve regeneration.

Considering the above, what is needed is a nerve coaptation apparatusthat addresses one or more of the shortcomings of microsutures andprevious coaptation devices.

SUMMARY OF THE INVENTION

The present invention generally provides an apparatus for coaptation offirst and second severed nerve segments. The apparatus includes aplurality of nerve-engaging features or “coupling members” that eachconnect to another coupling member to form “coupling pairs”. Thecoupling pairs are advantageously movable relative to each other topermit nerve swelling and inhibit nerve compression.

In one aspect, the present invention provides an apparatus forcoaptation of a first nerve segment separated from a second nervesegment. The apparatus includes a first coaptation member configured toextend about the first nerve segment and engage the first nerve segment.The apparatus further includes a second coaptation member configured toconnect to the first coaptation member and extend about the second nervesegment. The second coaptation member includes a first coupling memberand a second coupling member that are each configured to engage thesecond nerve segment to inhibit the second nerve segment from movingaway from the first nerve segment in a longitudinal direction. The firstcoupling member and the second coupling member are movable relative toeach other in a transverse direction substantially perpendicular to thelongitudinal direction to inhibit nerve compression.

In another aspect, the present invention provides an apparatus forcoaptation of a first nerve segment separated from a second nervesegment. The apparatus includes a first coaptation member configured toextend about the first nerve segment, and the first coaptation memberincludes a first coupling member configured to engage the first nervesegment. The apparatus further includes a second coaptation memberconfigured to extend about the second nerve segment, and the secondcoaptation member includes a second coupling member configured to engagethe second nerve segment. The second coupling member connects to thefirst coupling member to inhibit the first and second coaptation membersfrom moving apart in a longitudinal direction and to inhibit the firstand second nerve segments from moving apart in the longitudinaldirection. The first coupling member and the second coupling member aremovable in a transverse direction substantially perpendicular to thelongitudinal direction to inhibit nerve compression.

In yet another aspect, the present invention provides an apparatus forcoaptation of a first nerve segment separated from a second nervesegment. The apparatus includes a first coupling pair having a firstcoupling member configured to connect to the first nerve segment and asecond coupling member configured to connected to the second nervesegment. The first coupling member connects to the second couplingmember to engage the first nerve segment with the second nerve segment.The apparatus further includes a second coupling pair having a thirdcoupling member configured to connect to the first nerve segment and afourth coupling member configured to connected to the second nervesegment. The third coupling member connects to the fourth couplingmember to engage the first nerve segment with the second nerve segment.The first coupling pair is movable relative to the second coupling pairto inhibit compression of the first nerve segment and the second nervesegment.

The foregoing and other objects and advantages of the invention willappear in the detailed description that follows. In the description,reference is made to the accompanying drawings that illustrate apreferred configuration of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will hereafter be described with reference to theaccompanying drawings, wherein like reference numerals denote likeelements, and:

FIG. 1 is a side schematic view of a nerve coaptation apparatusaccording to the present invention;

FIG. 2 is a side perspective view of a first configuration of the nervecoaptation apparatus of FIG. 1 before connecting two coaptation members;

FIG. 3 is a side view of the first configuration of the nerve coaptationapparatus of FIG. 2 upon connecting the two coaptation members;

FIG. 4 is an end view of one of the coaptation members of FIG. 2;

FIG. 5 is a detail view of the area of one of the coaptation membersenclosed by line 5-5 of FIG. 2;

FIG. 6 is a side perspective view of a second configuration of the nervecoaptation apparatus of FIG. 1 before connecting two coaptation members;

FIG. 7 is a side perspective view of the second configuration of thenerve coaptation apparatus of FIG. 6 upon connecting the two coaptationmembers;

FIG. 8 is an end view of one of the coaptation members of FIG. 6;

FIG. 9 is a perspective view of two coupling members of the secondconfiguration of the nerve coaptation apparatus of FIG. 6;

FIG. 10 is a side perspective view of a third configuration of the nervecoaptation apparatus of FIG. 1 before connecting two coaptation members;

FIG. 11 is a side perspective view of the third configuration of thenerve coaptation apparatus of FIG. 10 upon connecting the two coaptationmembers;

FIG. 12 is a side perspective view of separation of two halves of one ofthe coaptation members of FIG. 10;

FIG. 13 is a flow chart setting forth steps of a pharmaceutical agentdelivery sequence conducted by the apparatus of FIG. 1;

FIG. 14A is a plot of sciatic function index scores versuspost-operative time for various types of nerve injuries andpharmaceutical agent sequences; and

FIG. 14B is a plot of foot fault asymmetry scores versus post-operativetime for various types of nerve injuries and pharmaceutical agentsequences.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIG. 1, the present invention provides an apparatus 50for coaptation of first and second severed nerve segments 10, 12.Generally, the apparatus 50 includes a first coaptation member 52 thatsurrounds and engages the first nerve segment 10 and a second coaptationmember 54 that surrounds and engages the second nerve segment 12. Thefirst and second coaptation members 52, 54 abut each other to coapt theends of the first and second nerve segments 10, 12. In addition, thefirst and second coaptation members 52, 54 include nerve-engagingfeatures or “coupling members” that each connect to a coupling member onthe opposite coaptation member 52, 54 to form “coupling pairs”. Thecoupling pairs are advantageously movable relative to each other topermit nerve swelling and inhibit nerve compression. Variousconfigurations of the apparatus 50 and the coupling members aredescribed below.

The coaptation members 52, 54 also receive one or more pharmaceuticalagents from an agent delivery device 56 to facilitate repair and fusionof the nerve segments 10, 12. Various pharmaceutical agents may be used,although advantageous pharmaceutical agents are described below.Regardless of the specific type used, the pharmaceutical agents aresubsequently evacuated to a collection device 58.

Turning now to FIGS. 2-5, a first configuration of the nerve coaptationapparatus 100 is shown. In this configuration, the first and secondcoaptation members 102, 104 are generally similar, and therefore onlythe first coaptation member 102 is described in detail herein.

The first coaptation member 102 includes a plurality of coupling members106, which may comprise various materials commonly associated withmedical devices, such as implantable, biodegradable, and non-neurotoxicpolymers and the like. Each of the coupling members 106 includes asemi-cylindrical wall 108, and together the walls 108 provide the firstcoaptation member 102 with a cylindrical shape for receiving the firstnerve segment 10. That is, the coupling members 106 together define openends 110, 112 through which the nerve segment 10 extends and an internalnerve passageway 114 that receives nerve segment 10. Furthermore, thecoupling members 106 together define a longitudinal direction of thecoaptation member 102 extending between the open ends 110, 112 andaligned with the longitudinal direction of the nerve segment 10.

To permit the coupling members 106 to move relative to each other, thefirst coaptation member 102 includes a plurality of expandable orflexible joints 116 connecting the sides of adjacent coupling members106. The flexible joints 116 may comprise various materials, such aselastically deformable, implantable, biodegradable, and non-neurotoxicpolymers and the like. In any case, the flexible joints 116 permit thecoupling members 106 to move in a transverse direction (that is, adirection perpendicular to the longitudinal direction within fivedegrees) relative to one another. Such relative motion between thecoupling members 106 advantageously permits nerve swelling (by up to,for example, 50 percent) and inhibits nerve compression.

The first coaptation member 102 includes several features to engage thefirst nerve segment 10 and the second coaptation member 104 proximatethe open end 110. To connect to the nerve segment 10, each of thecoupling members 106 includes a hooked epineurium pin 118. As the nameimplies, each epineurium pin 118 pierces the epineurium of the nervesegment 10. As such, the epineurium pins 118 inhibit the nerve segment10 from moving longitudinally relative to the coaptation member 102. Inaddition, the epineurium pins 118 hold the nerve segment 10 in anappropriate position for coaptation with the second nerve segment 12(that is, proximate the open end 110) when the coaptation members 102,104 are connected.

To connect the first coaptation member 102 to the second coaptationmember 104, each of the coupling members 106 includes two longitudinallyextending connection elements 120, 122 proximate the first open end 110.Half of the connection elements are tapering posts 120 and half of theconnection elements are holes 122. Each hole 122 receives one of thetapering posts 120 on the second coaptation member 104, and eachtapering post 120 is received in one of the holes 122 on the secondcoaptation member 104. In addition, each tapering post 120 may bepress-fittingly received in the corresponding hole 122 to provide a firmconnection between the coaptation members 102, 104. Such a connectionmay inhibit the coaptation members 102, 104 from moving apart in thelongitudinal direction once connected.

One or more of the coupling members 106 also include features to ensureproper angular alignment of the nerve segments 10, 12 (that is, properalignment of individual axons and the like). Specifically, on each ofthe coaptation members 102, 104, one of the coupling members 106includes a plurality of strips 124, 126, and 128 of different colors.When connecting the nerve segments 10, 12 to the coaptation members 102,104, respectively, common features of the nerve segments 10, 12 (forexample, fascicle patterns or the like) may be aligned with a specificstrip 124, 126, or 128. Then, when connecting the coaptation members102, 104 to each other, matching color strips 124, 126, and 128 on thecoaptation members 102, 104 are aligned to ensure that the features ofthe nerve segments 10, 12 are aligned. Furthermore, the coupling members106 could be translucent or transparent to permit the nerve segments 10,12 to be viewed therethrough.

During deployment, the coaptation members 102, 104 may be moved towardseach other and joined using a linear or hinged coupling applicator, suchas those used for vascular anastomoses. Other deployment devices mayalternatively be used.

After deployment, one or more pharmaceutical agents may be deliveredfrom the agent delivery device, through an inlet passageway 130 definedby one of the coupling members 106, and into the nerve passageways 114to facilitate repair and fusion of the nerve segments 10, 12. After aspecified amount of time, the pharmaceutical agents are evacuatedthrough an outlet passageway 132 defined by one of the coupling members106 and into the collection device.

The first configuration of the nerve coaptation apparatus 100 may bemodified in other manners that are not explicitly described above. Forexample, the coupling members 106 may include more or less than twoconnection elements 120, 122 and one epineurium pin 118 (for example,each coaptation member 102 and 104 may include twelve connectionelements 120, 122 and six epineurium pins 118). As another example, theinlet passageway 130 and outlet passageway 132 may be omitted, and gapsdefined by the flexible joints 116 and the sides of adjacent couplingmembers 106 may serve as inlet and outlet passageways.

Turning now to FIGS. 6-9, a second configuration of the nerve coaptationapparatus 200 is shown. In this configuration, the apparatus 200includes a first coaptation member and a second coaptation member 202,204 that are generally similar. As such, only the first coaptationmember 202 is described in detail herein. In general, the firstcoaptation member 202 permits nerve swelling and inhibits compression bydeploying a plurality of relatively movable coupling members. Thisaspect is described in further detail below.

The first coaptation member 202 may comprise various materials commonlyassociated with medical devices, such as non-neurotoxic polymers and thelike. The first coaptation member 202 includes a wall 206 that defines acylindrical shape for receiving the first nerve segment 10. That is, thewall 206 defines open ends 208, 210 through which the nerve segment 10extends and an internal nerve passageway 212 that receives nerve segment10. Furthermore, the coaptation member 202 defines a longitudinaldirection extending between the open ends 208, 210 and aligned with thelongitudinal direction of the nerve segment 10.

The first coaptation member 202 also supports connection elements 214,216, such as those described above, to connect to the second coaptationmember 204. That is, the coaptation member 202 includes a plurality oflongitudinally extending connection elements 214, 216 proximate thefirst open end 208. Half of the connection elements are tapering posts214 and half of the connection elements are holes 216. Each hole 216receives one of the tapering posts 214 on the second coaptation member204, and each tapering post 214 is received in one of the holes 216 onthe second coaptation member 204. In addition, each tapering post 214may be press-fittingly received in the corresponding hole 216 to providea firm connection between the coaptation members 202, 204. Such aconnection may inhibit the coaptation members 202, 204 from moving apartin the longitudinal direction once connected.

The first coaptation member 202 also includes inlet and outletpassageways 218, 220 to receive and evacuate one or more pharmaceuticalagents, respectively. In this configuration, the inlet and outletpassageways 218, 220 are defined adjacent to bridges 222 that connectopposite semi-cylindrical halves 224 of the coaptation member 202.

As described briefly above, the first coaptation member 202 releasablysupports a plurality of coupling members 226, 228 on the inner surfaceof the wall 206. The coupling members 226, 228 engage and hold the firstnerve segment 10 in contact with the second nerve segment 12. As such,the coupling members 226, 228 may comprise various materials commonlyassociated with medical devices, such as implantable, biodegradable, andnon-neurotoxic polymers and the like.

To engage and hold the first nerve segment 10 in contact with the secondnerve segment 12, half of the coupling members 226 have tapering shapesand act as epineurium pins that pierce the epineurium of the nervesegment 10. In addition, these coupling members 226 are fixedly receivedby a corresponding pin-receiving coupling member 228 of the secondcoaptation member 204. Similarly, each pin-receiving coupling member 228of the first coaptation member 202 fixedly receives one of theepineurium pin coupling members 226 of the second coaptation member 204.

After receiving the nerve segments 10, 12, connecting to each other, anddelivering and evacuating the pharmaceutical agents, the coaptationmembers 202, 204 detach from the coupling members 226, 228, for example,by breaking the bridges 222 and an adhesive connection between thecoaptation members 202, 204 and the coupling members 226, 228. Thecoupling members 226, 228 remain connected to each other and the nervesegments 10, 12. As such, the coupling members 226, 228 inhibit thenerve segments 10, 12 from moving apart in the longitudinal direction.However, each pair of coupling members 226, 228 is movable in thetransverse direction relative to the other pairs. The coupling members226, 228 thereby permit nerve swelling and inhibit compression.

Turning now to FIGS. 10-12, a third configuration of the nervecoaptation apparatus 300 is shown. The third configuration of theapparatus 300 shares many features with the second configuration of thenerve coaptation apparatus 200. For example, the coaptation members 302,304 may comprise various materials commonly associated with medicaldevices, such as non-neurotoxic polymers and the like. Furthermore, eachcoaptation member 302, 304 includes a plurality of connection elements306, 308 like those described above and a plurality of detachablysupported and nerve-engaging coupling members 310, 312 like thosedescribed above. Each coaptation member 302, 304 also includes inlet andoutlet passageways 314, 316 to receive and evacuate one or morepharmaceutical agents, respectively.

In contrast to the second configuration, each coaptation member 302, 304includes two separate semi-cylindrical halves 318 that are initiallyheld in abutment by a semi-cylindrical deployment element 320. As such,after connecting the nerve segments 10, 12 to the coupling members 310,312 and connecting the coaptation members 302, 304 to each other, thedeployment elements 320 are detached from the coaptation members 302,304 by, for example, moving the deployment elements 320 apart in thelongitudinal direction. Thereafter, and as shown in FIG. 12, thecoaptation member halves 318 are separated from each other, the couplingmembers 310, 312, and the nerve segments 10, 12 by moving apart in thetransverse direction.

For each of the above configurations, the coaptation members may providea range of sizes appropriate for use with digital nerve repair (about 1mm in diameter) up to brachial root repair (about 1 cm in diameter).

Turning now to FIGS. 13, 14A, and 14B and as briefly described above,the coaptation members may receive one or more pharmaceutical agentsfrom the agent delivery device to facilitate repair and fusion of thenerve segments. The agent delivery device may be one or more syringes(in the case of a single syringe, multiple agents may be separatelycompartmentalized), a manifold that automatically deliverspharmaceutical agents, or the like.

Regardless of the specific type of agent delivery device, thepharmaceutical agents preferably and advantageously include a sequenceof: 1) a hypotonic calcium-free solution (for example, a solution asshown below in Tables 1 and 2 applied for a period of about 60 secondsbefore evacuation); 2) antioxidants/inhibitors of membrane sealing (forexample, 2 mM melatonin or 100 μM USP methylene blue applied for aperiod of about 90 seconds before evacuation); 3) a lipid membranefusogen (for example, 5 g polyethylene glycol 2000 (PEG) dissolved in 5mL distilled water applied for about 90 seconds before evacuation); and;4) isotonic calcium-containing solution (for example, a solution asshown below in Tables 3-5 applied for a period of about 120-180 secondsbefore evacuation).

TABLE 1 Hypotonic calcium-free solution. Chemicals dissolved in 1000 mLdistilled water, buffering pH with HCl or NaOH, respectively, addeddrop-wise. Symbol Chemical Amount MW Factor mM/L species mOsm/L NaClSodium Chloride 5.7856 g 58.44 1 99 2 198 KCl Potassium Chloride 0.3728g 74.56 1 5 2 10.0 KH₂PO₄ Potassium 0.1634 g 136.09 1 1.2 2 2.4Phosphate MgSO₄ Magnesium Sulfate 0.1566 g 120.39 1 1.3 2 2.6 NaHCO₃Sodium Bicarbonate 2.1842 g 84.01 1 25 2 50.0 NaC₆H₇O₆ Sodium Ascorbate 1.981 g 198.1 1 10 2 20.0 C₆H₁₂O₆ Dextrose   1.8 g 180.16 1 9.9 1 10.0— Solution A (see    50 mL 95.21 85.49/10 8.55 3 25.7 Table 2) 273.7318.7

TABLE 2 Solution A. Dissolved in 500 mL distilled water. Symbol ChemicalAmount (g) MW Multiplicand mM/L Species mOsm/L MgCl₂ Magnesium 4.0795.21 2 85.49 3 256.47 Chloride

TABLE 3 Isotonic calcium-containing solution. Buffer pH with HCl orNaOH, respectively, added drop-wise. Mix cold. Symbol Chemical Amount MWmM/L Species mOsm/L — Solution B 475 mL 473.49 331.55 1 314.97 (seeTable 4) H₂O Distilled Water 475 mL 18 — — — Solution C 50 mL 111.0 2 36.0 (see Table 5) NaC₆H₇O₆ Sodium 1.981 g 198.1 10 2 20 AscorbateC₆H₁₂O₆ Dextrose 1.8 g 180.16 9.9 1 9.9 350.87

TABLE 4 Solution B. Chemicals dissolved in 4000 mL distilled water.Symbol Chemical Amount (g) MW Divisor mM/L Species mOsm/L NaCl Sodium61.024 58.44 4 261.05 2 522.1 Chloride KCl Potassium 3.139 74.56 4 10.52 21 Chloride KH₂PO₄ Potassium 1.374 136.09 4 2.52 2 5.04 PhosphateMgSO₄ Magnesium 1.318 120.39 4 2.74 2 5.48 Sulfate NaHCO₃ Sodium 18.39484.01 4 54.74 2 109.48 Bicarbonate 473.49 331.55 663.1

TABLE 5 Solution C. Dissolved in 1000 mL distilled water. SymbolChemical Amount (g) MW mM/L Species mOsm/L CaCl₂ Calcium 4.44 111.0 40 3120 Chloride

Alternatively, the hypotonic calcium-free solution may be additionallyapplied to the nerve after the antioxidants/inhibitors of membranesealing and before the lipid membrane fusogen to wash away USP methyleneblue stains on the nerve segments.

Data collected by the present inventors and partially illustrated inFIGS. 14A and 14B indicates that antioxidants/inhibitors of membranesealing, such as USP methylene blue and melatonin, maintain the axonalends of severed nerve segments in an open and vesicle-free stateappropriate for repair by a lipid membrane fusogen, such as PEG.Furthermore, these data also indicate that the above sequenceadvantageously improves recovery time and nerve function compared tomicrosutures, specifically by a factor of up to two and 40 percent infour months, respectively.

After the specified contact period with the nerve segments, eachpharmaceutical agent may be evacuated by applying vacuum pressure,permitting free drainage, capillary action (for example, by connectingthe outlet passageway to an absorbent surgical material), or the like.Furthermore, the actions of the delivery device and the collectiondevice can be coordinated, for example, via an electronic controller(not shown) and a plurality of valves (not shown), such that eachpharmaceutical agent contacts the nerve segments for the specifiedcontact period. Such a controller may also control the delivery pressureof the pharmaceutical agents. That is, the controller may provide theagents at a pressure sufficiently low to maintain contact of the ends ofthe nerve segments, and sufficiently high to ensure adequatedistribution of the chemicals over the nerve segments.

The pharmaceutical agent delivery sequence may be summarized as follows.

A method for treatment of a nerve, comprising the steps of:

delivering at least one of an antioxidant and an inhibitor of membranesealing to the nerve;

evacuating the at least one of the antioxidant and the inhibitor ofmembrane sealing away from the nerve;

delivering at least one lipid membrane fusogen to the nerve afterevacuating the at least one of the antioxidant and the inhibitor ofmembrane sealing; and

evacuating the at least one lipid membrane fusogen away from the nerve.

In some configurations, the at least one of the antioxidant and theinhibitor of membrane sealing includes one of USP methylene blue andmelatonin.

In some configurations, the at least one lipid membrane fusogen includespolyethylene glycol.

In some configurations, the method further comprises the steps of:

delivering at least one hypotonic calcium-free solution to the nerve;and

evacuating the at least one hypotonic calcium-free solution away fromthe nerve before delivering the at least one of the antioxidant and theinhibitor of membrane sealing.

In some configurations, the method further comprises the steps of:

delivering at least one isotonic calcium-containing solution to thenerve after evacuating the at least one lipid membrane fusogen; and

evacuating the at least one isotonic calcium-containing solution awayfrom the nerve.

In some configurations, the nerve includes a first segment severed fromand abutting a second segment, and each of the at least one of theantioxidant and the inhibitor of membrane sealing and the at least onelipid membrane fusogen are delivered to and evacuated away from thefirst segment and the second segment.

The pharmaceutical agents may be provided in a kit. Such a kit may besummarized as follows.

A kit for use in a pharmaceutical agent delivery sequence, comprising:at least one of an antioxidant and an inhibitor of membrane sealing; atleast one lipid membrane fusogen; and instructions indicating that thepharmaceutical agent delivery sequence includes at least one of theantioxidant and the inhibitor of membrane sealing followed by the atleast one lipid membrane fusogen.

From the above description, it should be apparent that the presentinvention provides a nerve coaptation apparatus that includes aplurality of nerve-engaging coupling pairs. The coupling pairs areadvantageously movable relative to each other to permit nerve swellingand inhibit nerve compression.

The various configurations presented above are merely examples and arein no way meant to limit the scope of this disclosure. Variations of theconfigurations described herein will be apparent to persons of ordinaryskill in the art, such variations being within the intended scope of thepresent application. In particular, features from one or more of theabove-described configurations may be selected to create alternativeconfigurations comprised of a sub-combination of features that may notbe explicitly described above. In addition, features from one or more ofthe above-described configurations may be selected and combined tocreate alternative configurations comprised of a combination of featureswhich may not be explicitly described above. Features suitable for suchcombinations and sub-combinations would be readily apparent to personsskilled in the art upon review of the present application as a whole.The subject matter described herein and in the recited claims intends tocover and embrace all suitable changes in technology.

1.-22. (canceled)
 23. A method of treating a mammal with a nerve in needof repair comprising the steps of: a) applying a hypotonic, calcium-freesaline solution to said nerve for a first period of time; b) concurrentwith or after step a), applying to said nerve a solution containing anantioxidant neuroprotectant for a second period of time; c) thenapplying a lipid membrane fusogen solution to said nerve for a thirdperiod of time; and d) applying to the nerve an isotonic,calcium-containing solution for a fourth period of time.
 24. The methodof claim 23, wherein said nerve is severed.
 25. The method of claim 23,wherein said mammal is a human patient.
 26. The method of claim 23,wherein the antioxidant neuroprotectant comprises melatonin or methyleneblue.
 27. The method of claim 23, wherein the hypotonic, calcium-freesolution comprises sodium chloride, potassium chloride, potassiumphosphate, magnesium sulfate, sodium bicarbonate, sodium ascorbate,and/or dextrose.
 28. The method of claim 23, wherein said lipid membranefusogen comprises polyethylene glycol (PEG).
 29. The method of claim 28,wherein the PEG is present at a concentration of from 100 to 500 mM. 30.The method of claim 23, wherein following the first, second, third andfourth periods of time, the respective solution is evacuated.
 31. Themethod of claim 23, wherein the first period of time is about 60seconds, the second period of time is about 90 seconds, the third periodof time is about 90 seconds and the fourth period of time is about 120to 180 seconds.
 32. The method of claim 23, wherein the lipid membranefusogen is applied for about 90 seconds before evacuation.
 33. Themethod of claim 23, wherein the isotonic, calcium-containing solution isapplied for about 120-180 seconds before evacuation.
 34. The method ofclaim 23, further comprising a further application of a hypotoniccalcium-free solution to the nerve after step b).
 35. The method ofclaim 23, wherein the solutions are contained within syringes.
 36. Themethod of claim 23, wherein the hypotonic, calcium-free saline and thesolution containing an antioxidant are comprised in separate barrels ofa double-barreled syringe.
 37. A kit for use in a pharmaceutical agentdelivery sequence, comprising at least one of an antioxidant and aninhibitor of membrane sealing; at least one lipid membrane fusogen; andinstructions indicating that the pharmaceutical agent delivery sequenceincludes at least one of the antioxidant and the inhibitor of membranesealing followed by the at least one lipid membrane fusogen.
 38. The kitof claim 34, wherein the kit comprises a hypotonic, calcium-free salinesolution, an antioxidant solution, a lipid membrane fusogen solution andan isotonic, calcium-containing solution, wherein said solutions arecomprises in separate containers.
 39. The kit of claim 38, wherein thesolutions are contained within syringes.
 40. The kit of claim 38,wherein the hypotonic, calcium-free saline solution and the solutioncontaining an antioxidant are comprised in separate barrels of adouble-barreled syringe.
 41. A method for treatment of a nerve,comprising the steps of: a) delivering at least one of an antioxidantand an inhibitor of membrane sealing to the nerve; b) evacuating the atleast one of the antioxidant and the inhibitor of membrane sealing awayfrom the nerve; c) delivering at least one lipid membrane fusogen to thenerve after evacuating the at least one of the antioxidant and theinhibitor of membrane sealing; and d) evacuating the at least one lipidmembrane fusogen away from the nerve.
 42. The method of claim 25 or 41,further comprising measuring the electrical conductance of the nervebefore and after said treatment.
 43. The method of claim 42 wherein themeasurement of nerve conductance is with a device capable of measuring acompound action potential in a nerve.